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Acute flaccid myelitis (AFM) is a condition that affects the nervous system, specifically the spinal cord, which can result from a variety of causes including viral infections. AFM is characterized by a sudden weakness in one or more arms or legs, along with loss of muscle tone and decreased or absent reflexes. Numbness or other physical symptoms are rare, although some patients may have pain in their arms or legs. In some cases, dysfunction of the nerves controlling the head and neck, resulting in such features as facial weakness, difficulty swallowing, or drooping of the eyes, may accompany the limb weakness.

AFM in 2016

CDC is working hard to understand what led to an increase in AFM cases in 2016. As of December 2016, 149 people in 39 states and DC were confirmed to have this serious illness.

CDC is concerned about AFM and the individuals and families affected. We are intensifying our efforts to figure out what causes AFM and puts people at risk.

CDC urges healthcare providers to be alert for and send information about AFM cases to their health departments. We remind the public to always practice general disease prevention steps, like washing your hands, staying up-to-date on vaccines, and protecting yourself from mosquito bites.